Apparatus having rotating chains or rings for carrying vertically hanging trays

ABSTRACT

An apparatus for carrying a plurality of vertically hanging trays includes a vertical rotating means comprising a first pair of rotating chains carrying the plurality of trays at respective tray apexes and a second pair of rotating chains carrying the trays at respective bases, the first and second pairs of rotating chains being operatively coupled. The apparatus may be used in a furnace, a cleaning apparatus and a combined furnace/cleaning apparatus as well as in medical and other applications.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a continuation in part application of Ser.No. 10/730,150 filed on Dec. 7, 2003, now U.S. Pat. No. 6,997,705, thedisclosure of which in incorporated herein in its entirety.

BACKGROUND OF THE INVENTION

The invention relates generally to furnace configurations for arrangingmechanical and electrical units to carry out heating and coolingprocesses for electronic component manufacturing, food processing, andmedical sterilization. More particularly, the invention relates to a newand improved apparatus for simplifying the processes for electroniccomponent manufacturing, materials processing, and medical applicationswhile reducing energy use and achieving time savings required for suchprocesses.

Conventional furnaces are limited by technical difficulties arising fromthe use of linear conveyors which are employed to carry objects throughthe furnace to perform several cycles of heating and cooling throughseveral chambers or zones. Specifically, conventional furnaces used inthe electronics industry for processing and soldering Printed CircuitBoard (PCB) assemblies are constructed by employing linear conveyors.The object to be heated is placed on the conveyor at an inlet of thefurnace and the conveyor then carries the object linearly through aseries of heating chambers with pre-set temperatures. Some chambers areequipped with heaters and fans to carry out the pre-heating or intensiveheating operations while subsequent chambers are equipped with fans toprovide a cooling process of the objects according to processrequirements. In this conventional configuration, energy is wasted dueto heat losses caused by hot air leaks from the multiple openings in theheat chambers that accommodate the entry and exit of the linearconveyor. Further heat losses are incurred as heated air continuouslyrises to the top of the heating chambers while the objects pass throughthe bottom of the heating chambers. Additionally, in a batch process,when the cooling and heating processes are performed in a singlechamber, the heating and cooling cycles often prolong the manufacturingprocesses because the processing cycles require considerable lengths oftime for the objects to cool and pre-heat before a next heating cyclemay begin. All of these limitations add to the cost and manufacturingcomplexities when a conventional furnace is employed.

U.S. Pat. No. 5,154,338 discloses an arrangement of heating units withfans in each chamber installed opposite one another above and below theconveyor to constitute a pair along a line and separated by a partialpartition so that all the boards can be carried through the chambersfrom one end (inlet) to another end (outlet). Therefore, at least twooperations are required to carry out the tasks of heating profileadjustment, board loading as well as unloading, and quality inspection.The heat generated in each chamber cannot be easily recovered and usedagain by other chambers unless a special and more costly heat recycledesign is implemented to improve the energy recycling. Anotherlimitation of the disclosed arrangement is the limited amount ofreduction that can be accomplished in reducing the inner gas consumptionby installing the disclosed partitions. The disclosed furnace does notresolve the problem of heat inefficiencies, as the main door of thefurnace has to be opened for each loading-unloading cycle. Consequently,the heat applied in the previous batch operation is lost as is the inertgas pumped into the chambers of the furnace. The furnace and the inertgas have to be heated again for each cycle for a period of time.

Another drawback of linear furnaces is that such furnaces are notsuitable for applications in offices and laboratories due to the volumeoccupied by the furnace. Due to the required space, installation of aprior art furnace in a medical laboratory or restaurant for foodprocessing is not feasible even though such furnaces would be quietconvenient and useful for heat treatment.

There is therefore a need for an apparatus that overcomes thelimitations of the prior art. There is also a need for an apparatus thatis configured for simpler, faster, more energy efficient and economicalmethods of carrying out heating processes required in variedapplications. There is a further need for an apparatus configurationthat is smaller, more convenient to operate, and that can be easilyadapted for use in different kinds of operational environments forbroader applications. There is also a need for an apparatus configuredto allow for simplified loading and unloading. There is a further needfor an apparatus that minimizes heat losses and reduces inert gasconsumption.

SUMMARY OF THE INVENTION

The present invention provides an apparatus having rotating chains orrings which may be enclosed in a furnace housing to enable asubstantially vertical rotational movement of objects within the furnacehousing to carry out different kinds of heat processes, coolingprocesses and cleaning processes in a single processing cycle. Specialmechanical designs are implemented to assure the objects for heating aremaintained at fixed orientations without slipping or shifting position.The losses of heat applied for performing the heat processes aresignificantly reduced because the loading and unloading processes can becarried out only once at the same location. Efficient utilization ofenergy is achieved, as the heating zone is located on the top portionsof the furnace where the hot air generated by the properly arrangedheater around the rotating cycle path migrates through convection to thetop portions of the chamber with the help of electric fans. Theinvention thus takes advantage of natural convention to reduce energyconsumption.

In accordance with the invention, one person is enabled to carry outboth the loading and unloading operations and temperature profileadjustments at one location. Additional benefit is realized because theheat generated in the lower section of the furnace is available at otherhigher portions of the furnace by natural convection or partial forceconvection to further enhance the effectiveness of the heatingprocesses.

In one aspect of the invention, an apparatus for carrying a plurality ofvertically hanging trays includes a vertical rotating means comprising afirst pair of rotating chains carrying the plurality of trays atrespective tray apexes and a second pair of rotating chains carrying thetrays at respective bases, the first and second pairs of rotating chainsbeing operatively coupled.

In another aspect of the invention, a furnace includes a housing formingan enclosure, a heating means for heating the enclosure, an openingformed in the housing, and a vertical rotating means disposed in theenclosure, wherein the vertical rotating means comprise a first pair ofrotating chains carrying a plurality of trays at respective tray apexesand a second pair of rotating chains carrying the plurality of trays atrespective tray bases.

These and other objects and advantages of the present invention will nodoubt become obvious to those of ordinary skill in the art after havingread the following detailed description of the preferred embodiment thatis illustrated in the various drawing figures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a perspective view of a furnace implemented with one pairof rotating chains and one pair of fixed rings in accordance with theinvention;

FIG. 2 shows a front elevation view of the furnace of FIG. 1 inaccordance with the invention;

FIG. 3 shows a perspective view of a furnace implemented with one pairof rotating rings and one pair of fixed rings in accordance with theinvention;

FIG. 4 shows a front elevation view of the furnace of FIG. 3 inaccordance with the invention;

FIG. 5 shows a perspective view of a furnace implemented with one pairof rotating elliptical chains and one pair of fixed elliptical rings inaccordance with the invention;

FIG. 6 shows a front view of the furnace of FIG. 5 in accordance withthe invention;

FIG. 7 shows a perspective view of a vertical rotational system disposedacross three levels of a hospital in accordance with the invention;

FIG. 8 is a side elevation view of the vertical rotational system ofFIG. 7 in accordance with the invention;

FIG. 9 shows a perspective view of a furnace implemented with one pairof rotating rings and one pair of fixed rings operable to implement acleaning system in accordance with the invention;

FIG. 10 is a side elevation view of the furnace of FIG. 9 in accordancewith the invention;

FIG. 11 is a perspective view of a vertical rotational systemimplemented with two elliptical pairs of rotating chains to implement acleaning system in accordance with the invention;

FIG. 12 is a side elevation view of the vertical rotational system ofFIG. 11 in accordance with the invention;

FIG. 13 is a perspective view of a furnace implemented with two pairs ofelliptical rotating chains to implement a PCB process including acleaning process in accordance with the invention;

FIG. 14 is a side elevation view of the furnace of FIG. 13 in accordancewith the invention;

FIG. 15 is a perspective view of a furnace implemented with two pairs ofcircular rotating chains in accordance with the invention;

FIG. 16 is a side elevation view of the furnace of FIG. 15 in accordancewith the invention;

FIG. 17 is a perspective view of a furnace implemented with one pair ofrotating rings and one pair of fixed rings including a heater and dryerin accordance with the invention;

FIG. 18 is a side elevation view of the furnace of FIG. 17;

FIG. 19 is a perspective view of a furnace implemented with two pairs ofcircular rotating chains to implement a cleaning process in accordancewith the invention;

FIG. 20 is a side elevation view of the furnace of FIG. 19;

FIG. 21 is a perspective view of a furnace implemented with one pair ofeyedropper shaped rotating chains and one pair of fixed rings inaccordance with the invention;

FIG. 22 is a side elevation view of the furnace of FIG. 20 in accordancewith the invention;

FIG. 23 is a perspective view of a furnace implemented with two pairs ofeyedropper shaped rotating chains in accordance with the invention; and

FIG. 24 is a side elevation view of the furnace of FIG. 23 in accordancewith the invention.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIG. 1 and FIG. 2 a furnace 200 includes a pair of chains210 and a pair of rings 220 disposed below the pair of chains 210. Amotor 230 having a gearbox is engaged to one chain or both chains todrive the pair of chains to rotate while the pairs of rings 220 are keptstationary. The pair of rings 220 is separated by a desired distance toprovide an open space within the furnace 200 to accommodate the pair ofchains 210 whose central portion is coupled to a rotary driver mechanismpowered by the motor 230. Furthermore, the axis line comprising the twofixed ring geometric centers are parallel and vertically below the axisline comprising the two rotating chain geometric centers.

A plurality of trays 240 include a horizontal bottom plate 240-B andside panels 240-S with top apex 240-A having two hanging points attachedand hung on the chains 210. The bottom plate 240-B is engaged andrestrained along the pair of rings 220 to assure that the horizontalbottom plate 240-B is continuously maintained horizontally as the pairsof chains 210 carry the trays 240 along a rotational trajectory. Thetrays 240 are engaged between the pairs of rotational chains 210 and thestationary rings 220 employing a four bar linkage mechanism such thatthe bottom plate 240-B can always orient along a horizontal plane tocarry objects to undergo process cycles. Special arrangements are madebetween the chains 210 to rings 220 on each side with an offset at adefined space so a drive bar can be used to connect with both unitswithout any interference during cycle rotation. The furnace 200 furtherincludes a heat exchanger 250 for controlling the temperature of thefurnace. A flux foam pot 260 is disposed on a bottom of the furnace forcarrying out flux coating on the bottom side of PCB boards. Awave-soldering unit 265 is placed on a top portion of the furnace.

Referring to FIG. 2, the furnace 200 is enclosed in a housing 270 with aloading/unloading opening 280 for loading the objects forheating/cooling onto the trays 240 and to remove the objects after theheating/cooling processes are completed. The housing 270 includes a topportion removable from a bottom portion. The rotating mechanismimplemented by the motor 230 and the pair of chains 210 rotates theobjects for heating placed onto the trays 240 from a cold zone disposedat a fourth quadrant range, i.e., at a lower portion of the enclosurehousing 270 to a hot zone disposed on an upper portion of the enclosurehousing 270 for carrying out the heating processes on the objects. Themotor 230 can be controlled to rotate the objects between the cold zoneand the hot zone alternatively to do soldering reflow and wave solderingin the hot zone and solidifying the solder material between theleads/pins and the pads/holes of electronic parts in the cold zone.

In FIG. 1, FIG. 2, and FIG. 3, the heavy continuous lines representspecial function modules including soldering pots, flux foam generatorsand heat exchangers. The heavy dashed lines represent the furnacehousing. The continuous lines represent the trays. The fine continuouslines represent the skeleton structure of the furnace including therings and chains. The heating units are not shown in the drawings butone of ordinary skill in the art will appreciate that such heating unitsare needed to implement a plurality of specific applications.

The furnace 200 of the invention provides a furnace operable to performboth heating and cooling in a single processing cycle carried out atdifferent locations inside a confined rotating volume within theenclosure housing 270. A simple partition is achieved by naturalconvection and enhanced by the tray movement acting as a propeller.Fewer heating units are disposed along the tray movement path so thefurnace temperature profile can be set for infinitesimal heating changeor for a rapid heating change.

The installation of the heat exchanger 250 diverts unnecessary heat fromthe furnace first quadrant to the third quadrant for preheat purposes.This makes the cooling process easier in the first quadrant.

In a preferred embodiment, the furnace 200 is provided with a pluralityof radially extending beams with one end connected to a small innercircle that is attached to a furnace wall and the other end, generallyreferred to as an external point, for supporting rotation of the chain210. These external points are also restrained by a cross bar installedbetween two nearby beams. The final shape of the support structure ispreferably a spider web form.

The objects or work pieces are loaded onto the trays 240. The trays 240have their apexes 240-A hingedly attached to the rotating chain 210 onthe top ring pair and the base connected to the lower ring pair 220 viaa sliding mechanism. This linkage can provide a stable and steadyrotating movement of the trays 240 by restraining a middle point of thelateral sides of the base 240-B. For a PCB process, the performance ofboth the soldering reflow and wave soldering can be carried out in asingle processing cycle as the trays 240 rotate in the hot zone and thesolder solidification takes place as the trays 240 are rotated to thecool zone.

Another benefit of the furnace 200 is the smooth operation of theloading and unloading of the objects onto the trays 240 due to therotational movement of the trays 240. Special mechanisms forautomatically loading and unloading may be conveniently designed tocomply with the rotational movement of the trays 240 to place and removethe objects to and from the trays 240 through the opening 280.Alternatively, an operation may place and remove the objects.

The furnace 200 develops a temperature gradient along the elevation ofthe furnace 200 and increases in the heating effect may be achieved byadding heating units along the tray movement path at intended areas.Heat can be kept in the upper quadrants to thereby reduce the energyconsumption and use of inert gases of the furnace 200. For PCB solderingpurposes, by employing the furnace 200, the drag material produced inthe wave soldering oven can be reduced to a minimum level or evendiminished to a level of zero when proper designs are implemented withinert gas or reduced atmosphere.

The furnace 200 can be used for a plurality of applications with theaddition of required devices, equipment, and modules. The compact sizeand ease of operation of the furnace 200 allows the furnace 200 to beeasily and conveniently built for operation in an office or smalllaboratory. The furnace 200 thus can be employed for applications suchas medical, food processing, and any industrial applications thatrequire heat processing.

FIG. 3 and FIG. 4 show another embodiment of the invention including afurnace 300 having a pair of vertically rotating rings 310 and a pair offixed rings 320. A motor 330 drives the pair of rotating rings 310. Thepair of rotating rings 310 carry trays 340. The pair of fixed rings 320are separated by a desired distance to provide an open space within thefurnace 300 to accommodate the pair of rotating rings 310 whose centralportion is coupled to a rotary driver mechanism powered by the motor330. Furthermore, the axis line comprising the two fixed ring geometriccenters are parallel and vertically below the axis line comprising thetwo rotating ring geometric centers.

The pair of fixed rings 320 keep the trays 340 in a vertical positionwhen the trays 340 are rotated from the first quadrant through thefourth, third and second quadrants. Alternatively, the trays 340 may berotated in a counter-clockwise direction through the first, second,third, and fourth quadrants.

The motor 330 includes a gearbox and is engaged to one or both rotatingrings 310 to rotate the rotating rings 310 while the fixed rings 320 arestationary. A plurality of trays 340 include a horizontal bottom plate340-B and side panels 340-S with a top apex 340-A having two hangingpoints attached and hung on the rotating rings 310. The bottom plate340-B is slidingly engaged and restrained along the pair of fixed rings320 to assure that the horizontal bottom plate 340-B is continuouslymaintained in a horizontal plane as the pairs of rotating rings 310carry the trays 340 along a rotational trajectory. The trays 340 areengaged between the pairs of rotating rings 310 and the fixed rings 320employing a four bar linkage mechanism such that the bottom plate 340-Bcan always orient itself along the horizontal plane to carry objectsundergoing a process cycle. Special arrangements are made between therotating rings 310 and the fixed rings 320 on each side with an offsetat a defined space so a drive bar can be used to connect with both unitswithout any interference during cycle rotation.

The furnace 300 further includes a heat exchanger 350 for controllingthe temperature of the furnace 300. A flux foam pot 360 is disposed on abottom of the furnace 300 for carrying out flux coating on the bottomside of a PCB. A wave-soldering unit 365 is disposed at a top portion ofthe furnace 300.

FIG. 5 and FIG. 6 show another embodiment of the invention including afurnace 400 having vertically rotating elliptical chains 410 and a pairof fixed elliptical rings 420. The pair of rotating chains 410 is drivenby a motor 430 and carries trays 440. A furnace housing 470 encloses thepair of rotating chains 410 and the fixed rings 440. The pair ofrotating chains carries the trays 440 while bottom portions of the trays440 are slidingly attached to the pair of fixed rings 420. Thisconfiguration keeps the trays 440 in a vertical orientation when thetrays 440 are rotated with the pair of rotating chains 410 along avertically ellipse-shaped trajectory.

The motor 430 includes a gearbox engaged to one or both or the rotatingchains 410 to drive the pair of rotating chains 410 to rotate while thepairs of fixed rings 420 are kept stationary. A plurality of trays 440include a horizontal bottom plate 440-B and side panels 440-S with a topapex 440-A having two hanging points attached and hung on the rotatingrings 410. The bottom plate 440-B is slidingly engaged and restrainedalong the pair of fixed rings 420 to assure that the horizontal bottomplate 440-B is continuously maintained in a horizontal plane as thepairs of rotating rings 410 carry the trays 440 along an ellipticalrotational trajectory. The trays 440 are engaged between the pairs ofrotating rings 410 and the fixed rings 420 employing a four bar linkagemechanism such that the bottom plate 440-B can always orient itselfalong the horizontal plane to carry objects undergoing a process cycle.Special arrangements are made between the rotating rings 410 and thefixed rings 420 on each side with an offset at a defined space so adrive bar can be used to connect with both units without anyinterference during cycle rotation.

The furnace 400 includes a heat exchanger 450 for controlling thetemperature of the furnace 400. A flux foam pot 460 is disposed on abottom of the furnace 400 for carrying out flux coating on the bottomside of a PCB. A wave-soldering unit 465 is disposed in a top portion ofthe furnace 400.

With reference to FIG. 7 and FIG. 8, a vertical rotating structure inaccordance with the invention can be implemented with differentfunctional modules to perform special processes such a patient handlinginside a hospital. The hospital comprises three levels, a basement level770, a ground level 760, and a second floor level 750. The verticalrotating structure includes a pair of rotating chains 710 and a pair offixed rings 720. The pair of rotating chains 710 and the pair of fixedrings 720 may be circular or elliptical. A motor 730 is operably engagedto one or both rotating chains 710. A plurality of trays 740 couple therotating chains 710 to the fixed rings 720 as in previously describedembodiments. The trays 740 may include beds.

A patient 780 may be placed on a tray 740 in an emergency loading sideof the ground level 760 and prepared for subsequent processes. Therotating chains 710 may then be rotated to position the tray includingthe patient 780 in an X-ray/MRI station on the basement level 770. Afterreceiving an X-ray or MRI, the tray 740 may be rotated to a cleaning andsterilization station on the ground floor 760. Following a cleaning andsterilization process the tray 740 may be rotated to a surgical stationon the second floor 750. It can be seen that the patient does not haveto be moved from his bed during the performance of the variousprocesses. This is especially advantageous for patients with spinalchord injuries. Furthermore, if the X-ray and MRI do not show an injuryrequiring surgery, the patient may be removed from the tray 740 at thecleaning and sterilization station on the ground level 750.

In another aspect of the invention, the patient may be substituted withan automobile in an automobile repair station, a plant in a greenhouse,and a drug or chemical in a biotechnology facility. Each of three levelsmay be utilized for various purposes requiring particular conditionssuch as environmental conditions.

A cleaning system for washing printed circuit boards is shown in FIG. 9and FIG. 10. A pair of rotating rings 910 and a pair of fixed rings 920are disposed within a housing 900. A motor 930 is operatively engaged tothe rotating rings 910 and a plurality of trays 940 are linked to therotating rings 910 and the fixed rings 920 as previously described. Anarray of spray nozzles 970 is disposed in an upper portion of thehousing 900. The sprayed material, which may include water, is gatheredby a collector 975 formed of sheet metal and disposed under the array ofspray nozzles 970 in such manner that the material sprayed is directedto a collection tank 990 after being used to spray printed circuitboards disposed on the trays 940. A door 980 provides forloading/unloading of the printed circuit boards onto the trays 940. Thedoor 980 may be disposed in any place convenient for theloading/unloading of the trays 940 including a top portion of thehousing 900. A plurality of dryer fans 985 are disposed in the housingto dry the printed circuit boards as they pass between and near thedryer fans 985.

The collection tank 990 may include two sections. One section maycollect water from the collector 975 and another section may filter,ionize balance and chemically neutralize the collected water for reuseby the spray nozzles 990.

With reference to FIG. 11 and FIG. 12, the cleaning system isimplemented using a pair of running chains 1110 and a pair ofsynchronized chains 1120 housed in a housing 1100. The pair of runningchains 1110 and the pair of synchronized chains 1120 are coupled using atiming belt or chain 1135. A bar 1125 extending between a tray apex1140-A and a tray bottom portion 1140-B provides for smoother rotationof the trays 1140 and provides for increased synchronization betweenmovement of the running chains 1110 and the synchronized chains 1120. Amotor 1130 may include a stepper motor for precise positioning of thetrays 1140 within the housing 1100. In addition to an array of spraynozzles 1170, a collector 1175, a loading/unloading door 1180, acollection tank 1190, and a plurality of dryer fans 1185, the cleaningsystem includes a heat exchanger 1150 for distributing heat within thehousing 1100.

As shown in FIG. 13 and FIG. 14, a housing 1200 includes a pair ofirregularly shaped running chains 1210 and a pair of irregularly shapedsynchronized chains 1220 coupled together by means of a timing chain orbelt 1235. A motor 1230 is coupled to the pair of running chains 1210. Aplurality of trays 1240 are coupled to the pair of running chains 1210and the pair of synchronized chains 1220 as previously described. A bar1245 extends between a tray apex 1240-A and a tray bottom portion1140-B. The housing includes a first heat exchanger 1250 and a secondheat exchanger 1255, an array of nozzles 1270 disposed in an uppercorner of the housing 1200, and a collector 1290 disposed under thearray of nozzles 1270 for directing liquid into a collection tank 1290.The housing further includes a flux foaming unit 1260 disposed on abottom of the housing 1200, a solder pot 1265 disposed in an uppercorner of the housing 200 opposite the array of nozzles 1270, and aplurality of dryer fans 1285 for drying objects on the trays 1240. Aprinted circuit board process including fluxing and soldering andcleaning is achieved by this design.

With reference to FIG. 15 and FIG. 16, a furnace includes a housing 1300having a pair of running chains 1310 and a pair of synchronized chains1320 coupled by means of a timing chain or belt 1335. A motor 1330 iscoupled to the pair of running chains 1310. The furnace also includes aheat exchanger 1350, a flux foaming unit 1360, a solder pot 1365 and adoor for loading and unloading objects into and out of the furnace. Thepair of running chains 1310 and the pair of synchronized chains 1320 areof circular configuration.

FIG. 17 and FIG. 18 show a furnace including a housing 1700 having apair of rotating rings 1710 and a pair of fixed rings 1720. A motor 1730is coupled to the pair of rotating rings 1710 and a plurality of trays1740 are coupled to the pair of rotating rings 1710 and the pair offixed rings 1720 as described previously. A heater 1725 is showndisposed at a top portion of the housing 1700. A flux foaming pot 1760is disposed at a bottom of the housing 1700 and a solder pot 1765 isdisposed at a top of the housing 1700. A heat exchanger 1750 providesheat exchange and a plurality of dryer fans 1785 dry the objects on thetrays 1740. A door 1780 is provided to allow loading and unloading ofthe trays as well as access to the interior of the housing 1700.

With reference to FIG. 19 and FIG. 20, a cleaning system includes ahousing 1900 having a pair of running chains 1910 and a pair ofsynchronized chains 1920. A timing chain or belt 1935 couples the pairof running chains 1910 and the pair of synchronized chains 1920. A bar1925 extending between a tray apex and a tray bottom portion providesfor smoother rotation of the trays 1940 and provides for increasedsynchronization between movement of the running chains 1910 and thesynchronized chains 1920. A motor is coupled to the pair of runningchains 1910. The plurality of trays 1940 are coupled between the pair ofrunning chains 1910 and the pair of synchronized chains 1920 aspreviously described. An array of stray nozzles 1970 are disposed in atop portion of the housing 1900 and spray from the stray nozzles 1970 iscollected by a collector 1975. The collected spray is directed to acollection tank 1990. A plurality of dryer fans 1985 are disposed in thehousing 1900 to dry objects on the trays 1940.

FIG. 21 and FIG. 22 show a combined furnace and cleaning system in ahousing 2100 including a pair of rotating chains 2110 and a pair offixed rings 2120. A motor 2130 is coupled to the pair of rotating chains2110 and a plurality of trays 2140 are coupled to the pair of rotatingchains 2110 and the pair of fixed rings 2120 as previously described.The pair of rotating chains 2110 and the pair of fixed rings 2120 areteardrop shaped to provide space for each of the furnace and cleaningprocesses. A flux foaming unit 2160 is disposed on a bottom of thehousing 2100 on a left hand side thereof and a solder pot 2165 isdisposed on a top portion of the housing 2100 on the left hand sidethereof. A heat exchanger 2155 is provided. An array of spray nozzles2170 is disposed on a top portion of the housing 2100 on a right handside thereof. A collector 2195 is disposed under the array of spraynozzles 2170 to collect material sprayed and direct it to a collectiontank 2190 disposed on the bottom of the housing 2100 on a right handside thereof. A plurality of dryer fans 2185 are disposed on the righthand side of the housing 2100 to dry objects on the trays 2140.

With regard to FIG. 23 and FIG. 24, a combined furnace and cleaningsystem in a housing 2300 including a pair of running chains 2310 and apair of synchronized chains 2320. A timing chain or belt 2335 couplesthe pair of running chains 2310 and the pair of synchronized chains2320. A bar 2345 extending between a tray apex and a tray bottom portionprovides for smoother rotation of the trays 2340 and provides forincreased synchronization between movement of the running chains 2310and the synchronized chains 2320. A motor 2330 is coupled to the pair ofrunning chains 2310 and a plurality of trays 2340 are coupled to thepair of running chains 2310 and the pair of synchronized chains 2320 aspreviously described. The pair of running chains 2310 and the pair ofsynchronized chains 2320 are teardrop shaped to provide space for eachof the furnace and cleaning processes. A flux foaming unit 2360 isdisposed on a bottom of the housing 2300 on a left hand side thereof anda solder pot 2365 is disposed on a top portion of the housing 2300 onthe left hand side thereof. Heat exchangers 2350 and 2355 are provided.An array of spray nozzles 2370 is disposed on the top portion of thehousing 2300 on a right hand side thereof. A collector 2395 is disposedunder the array of spray nozzles 2370 to collected material sprayed anddirect it to a collection tank 2390 disposed on the bottom of thehousing 2300 on a right hand side thereof. A plurality of dryer fans2385 are disposed on the right hand side of the housing 2300 to dryobjects on the trays 2340.

In another aspect of the invention, the bar extending between a trayapex and a tray bottom portion to provide for smoother rotation of thetrays may be eliminated in cases where synchronization is not needed. Inthis case, a pair of running chains may be coupled to a pair of drivenchains coupled by a timing chain or belt. The driven chains are drivenby a motor.

The apparatus having rotating chains or rings for carrying verticallyhanging trays of the invention provides for a cheaper, simpler, faster,and more energy efficient apparatus of carrying out heating processesrequired in varied applications. The apparatus is smaller, moreconvenient to operate, and can be easily adapted for use in differentkinds of operational environments for broader applications such as inhospitals.

Some of the uses of the apparatus and its various configurations aresummarized in the table below. TABLE 1 Shape/Format Circle EllipseTeardrop Irregular Rotating Ring Furnace and & Stationary Ring CleanerRunning Furnace Furnace Furnace and Furnace and Chain & and Cleaner andCleaner Cleaner and Furnace/ Cleaner and Stationary and Medical andMedical Cleaner Furnace/Cleaner Ring Applications Applications andMedical and Medical Applications Applications Running Furnace FurnaceFurnace and Furnace and Chain & and Cleaner and Cleaner Cleaner andCleaner and Synchronized and Medical and Medical Furnace/CleanerFurnace/Cleaner Chain Applications Applications and Medical and MedicalApplications Applications Running Furnace Furnace Furnace and Furnaceand Chain & and Cleaner and Cleaner Cleaner and Cleaner and Driven Chainand Medical and Medical Furnace/Cleaner Furnace/Cleaner ApplicationsApplications and Medical and Medical Applications Applications

1. An apparatus for carrying a plurality of vertically hanging trayscomprising: a vertical rotating means comprising a first pair ofrotating chains carrying the plurality of trays at respective trayapexes and a second pair of rotating chains carrying the trays atrespective bases, the first and second pairs of rotating chains beingoperatively coupled.
 2. The apparatus of claim 1, wherein the first andsecond pairs of rotating chains have geometric centers vertically offsetfrom each other.
 3. The apparatus of claim 1, wherein the plurality oftrays are attached to the first and second pairs of rotating chains by afour bar linkage.
 4. The apparatus of claim 1, wherein the verticalrotating means is disposed in a housing having an opening.
 5. Theapparatus of claim 4, wherein the plurality of trays are alternativelyaccessible through the opening.
 6. The apparatus of claim 4, furthercomprising a furnace apparatus and a cleaning apparatus disposed in thehousing.
 7. The apparatus of claim 6, wherein the furnace apparatuscomprises a heat source, a flux foaming pot and a solder pot.
 8. Theapparatus of claim 6, wherein the cleaning apparatus comprises an arrayof spray nozzles, a collector and a collection tank.
 9. The apparatus ofclaim 1, wherein the vertical rotating means further comprise a motorcoupled to the first pair of rotating chains.
 10. The apparatus of claim1, wherein the first and second pairs of rotating chains are circular.11. The apparatus of claim 1, wherein the first and second pairs ofrotating chains are elliptical.
 12. The apparatus of claim 1, whereinthe first and second pairs of rotating chains are of irregular shape.13. The apparatus of claim 1, wherein the first and second pairs ofrotating chains are teardrop shaped.
 14. The apparatus of claim 1,wherein the first pair of rotating chains comprise a running chaindriven by a motor and the second pair of rotating chains comprise adriven chain coupled to the first pair of rotating chains by a timingbelt.
 15. The apparatus of claim 1, wherein the first pair of rotatingchains comprise a running chain driven by a motor and the second pair ofrotating chains comprise a synchronized pair of rotating chains coupledto the first pair of rotating chains by a timing belt and a barextending between a tray apex and a tray bottom portion.
 16. A furnacecomprising: a housing forming an enclosure; a heating means for heatingthe enclosure; an opening formed in the housing; and a vertical rotatingmeans disposed in the enclosure, wherein the vertical rotating meanscomprise a first pair of rotating chains carrying a plurality of traysat respective tray apexes and a second pair of rotating chains carryingthe plurality of trays at respective tray bases.
 17. The furnace ofclaim 16, wherein the first and second pairs of rotating chains havegeometric centers vertically offset from each other.
 18. The furnace ofclaim 16, further comprising a cleaning apparatus disposed in thehousing.
 19. The furnace of claim 18, wherein the cleaning apparatuscomprises an array of spray nozzles, a collector and a collection tank.20. The furnace of claim 16, wherein the first pair of rotating chainsis disposed in a top portion of the enclosure and the second pair ofrotating chains is disposed in a bottom portion of the enclosure.